For all interested people:
Just drop me a mail, DIGITEC in the subject, I am willing to sell some.
franzfgysi at bluewin.ch
They are heavier and bigger and therefore more expensive for shipment.
I think a price of 100US$ per pair including shipping will also be fair.
First come, first served!
Sorry, I really dont want to turn this thread into a sales thread. In fact, it would be more interesting for me, to offer it on eBay...
Kind regards
Franz
Just drop me a mail, DIGITEC in the subject, I am willing to sell some.
franzfgysi at bluewin.ch
They are heavier and bigger and therefore more expensive for shipment.
I think a price of 100US$ per pair including shipping will also be fair.
First come, first served!
Sorry, I really dont want to turn this thread into a sales thread. In fact, it would be more interesting for me, to offer it on eBay...
Kind regards
Franz
DIGITEC
Franz,
I also interested in DIGITEC
I can't send you e'mail directly from thisd thread.
Please send me you pm to busdar@belam.lt
Thanks in advance Darius
Franz,
I also interested in DIGITEC
I can't send you e'mail directly from thisd thread.
Please send me you pm to busdar@belam.lt
Thanks in advance Darius
Here the measurements of a Digitec (blue line):
Nearby like a simple wire
The square at 1kHz (red line) looks a little bit different (how could a tranny transfer the DC part of the square?), but in my opinion this is also in the size of a measurement error.
Franz
P.S.
Please stay in mailcontact with me, should you want a pair of this. Dont post it here, to not completely overload the thread. Availability is very limited right now! I unsoldered all 16 but I save 4 for my own DAC's
An externally hosted image should be here but it was not working when we last tested it.
Nearby like a simple wire
The square at 1kHz (red line) looks a little bit different (how could a tranny transfer the DC part of the square?), but in my opinion this is also in the size of a measurement error.
An externally hosted image should be here but it was not working when we last tested it.
Franz
P.S.
Please stay in mailcontact with me, should you want a pair of this. Dont post it here, to not completely overload the thread. Availability is very limited right now! I unsoldered all 16 but I save 4 for my own DAC's
... uuups, not to quick!
I just measured one of the Digitec's DC wise:
only about 7 Ohm.
What could be to low for this application.
I'll send out two pairs and we wait for the results. And I will compare soon with Lundahl LL1690. I think I will prepare a rotary switch for direct comparison.
Franz
I just measured one of the Digitec's DC wise:
only about 7 Ohm.
What could be to low for this application.
I'll send out two pairs and we wait for the results. And I will compare soon with Lundahl LL1690. I think I will prepare a rotary switch for direct comparison.
Franz
I really dont know the theory good enough, to say if it is a problem or not, the low DC resistance.
Just to try, I soldered a 47uF bipolar Elna cap in series with the trannies input, to block DC.
I measured it: no remarkable difference.
I just listen music: no difference, if I bridge the cap or not.
Franz
Just to try, I soldered a 47uF bipolar Elna cap in series with the trannies input, to block DC.
I measured it: no remarkable difference.
I just listen music: no difference, if I bridge the cap or not.
Franz
To not dissapoint people who already bought Studer's from me: I offer everyone who purchased up to now from me trannies, to get two of this Digitec's for only the shipping cost (15$).
Hello Franz,
I would also like a pair of those Digitec transformers.
Please send me an email and let me know were to send the payment.
Do you accept paypal.
Please let me know.
Thanks.
Hello Franz,
I would also like a pair of those Digitec transformers.
Please send me an email and let me know were to send the payment.
Do you accept paypal.
Please let me know.
Thanks.
Hafp
It seems like you are to late, I am sorry.
I try to get in contact with the others.
Franz
P.S.
In the meantime, I prepared a switch. And I can confirm, they sound great, both the Studers and the Digitecs. A very very small difference. A little bit more bass with the Digitecs like we have seen in the measurements, but a little bit better voices (Marla Glen) with the Studers.
/Edit
After listening and switching for and back: for classical music, voices and strings I prefer the Studers. For rock and pop I prefer the Digitecs, specially with Yello
It seems like you are to late, I am sorry.
I try to get in contact with the others.
Franz
P.S.
In the meantime, I prepared a switch. And I can confirm, they sound great, both the Studers and the Digitecs. A very very small difference. A little bit more bass with the Digitecs like we have seen in the measurements, but a little bit better voices (Marla Glen) with the Studers.
An externally hosted image should be here but it was not working when we last tested it.
/Edit
After listening and switching for and back: for classical music, voices and strings I prefer the Studers. For rock and pop I prefer the Digitecs, specially with Yello
After one hour of listening, I am happy to have prepared the rotary switch.
The difference is sooo small, it would be impossible for me to decide without immediate switching.
O.K., the little difference in the bass area.
But my conclusion: the low DC resistance of the Digitec trannies is absolutely irrelevant in this application.
I am looking forward to attach the third trannie, a LL1690, to the switch soon.
I am totally convinced now, that an output trannie is the best solution for a CS4398 DAC.
Franz
The difference is sooo small, it would be impossible for me to decide without immediate switching.
O.K., the little difference in the bass area.
But my conclusion: the low DC resistance of the Digitec trannies is absolutely irrelevant in this application.
I am looking forward to attach the third trannie, a LL1690, to the switch soon.
I am totally convinced now, that an output trannie is the best solution for a CS4398 DAC.
Franz
Hello Udo
Thanks, you will get two Studers.
About your question about the lundahls: I am waiting for delivery and cannot compare it yet.
The output level is 99% of the output level of the CS4398: line level.
@mush and @xaudiox: I sent you a pm, please get in contact with me for the Digitec's wich I reserved for you.
Kind regards
Franz
/Edit
Experience does also show me: an output trannie for the CS4398 is able to drive long cables without any problem! When I attach a 680pF Styroflex cap in parallel to the output, then I dont remark any difference. Conclusion: this solution can drive capacitive loads.
Thanks, you will get two Studers.
About your question about the lundahls: I am waiting for delivery and cannot compare it yet.
The output level is 99% of the output level of the CS4398: line level.
@mush and @xaudiox: I sent you a pm, please get in contact with me for the Digitec's wich I reserved for you.
Kind regards
Franz
/Edit
Experience does also show me: an output trannie for the CS4398 is able to drive long cables without any problem! When I attach a 680pF Styroflex cap in parallel to the output, then I dont remark any difference. Conclusion: this solution can drive capacitive loads.
I modified the PLL filter to the correct values. BTW: the correct values are printed on the PCB...
Then I tried the first time the SPDIF input: only noise
After fiddeling around with the input jumpers, I touched the jumpers during operation of the DAC: and the relay switched the input and sound is coming out!
My seller did not document this feature, specialy not the "S1" connections.
It seems to me, that adding a short contact toggle switch of the simplest version will switch the inputs!
I will ask again the seller about documentation of this feature.
Kind regards
Franz
Then I tried the first time the SPDIF input: only noise
After fiddeling around with the input jumpers, I touched the jumpers during operation of the DAC: and the relay switched the input and sound is coming out!
An externally hosted image should be here but it was not working when we last tested it.
My seller did not document this feature, specialy not the "S1" connections.
It seems to me, that adding a short contact toggle switch of the simplest version will switch the inputs!
I will ask again the seller about documentation of this feature.
Kind regards
Franz
udovdh said:
With the Lundahl you will have slightly less gain than with the op amp. Not a lot. I didn't measure it.
If some find the cost of the Lundahl LL1690 too high ($125 ea), you can use the LL1527XL which cost less ($76 ea ) and is supposed to be really great.
I' m happy that I gave you the "disease" to use output transformers with this dac.
Peoples who try it never return to any other topology.
I made comparaison with really big high end dacs and I would keep mine.
I will have a new one with upsampling board today and I will give you my feeling about the sound with upsampling.
Franz Gysi said:I modified the PLL filter to the correct values. BTW: the correct values are printed on the PCB...
Then I tried the first time the SPDIF input: only noise
After fiddeling around with the input jumpers, I touched the jumpers during operation of the DAC: and the relay switched the input and sound is coming out!
My seller did not document this feature, specialy not the "S1" connections.
It seems to me, that adding a short contact toggle switch of the simplest version will switch the inputs!
I will ask again the seller about documentation of this feature.
Kind regards
Franz
Hi Frantz,
I am using the exact same board as you and also miss the documentation for the input switching. I would like to install a simple 3 position switch that will enable input switching between Coax/Optical/USB. Duplicating the jumpers with two switches to select the input is probably not the way to go. Please post your findings on this to the forum.
Thanks
ronenash
New dac with upsampling
The upsampling dac with Lundahls is now playing
As it is brand new, there will be a broken in time to do. I replaced the cheap RCA input with a BNC 75 ohm
I'm really surprized by the sound as is. I was afraid that the upsampling mode create somewhat a hard sound but it seems that the sound is great .
I will live sometime with this dac as is and later I will add an input digital transformer to try.
How can they sell at such a low price a board like this one ? This is really a good quality board with good parts
I made a comparaison with the other model which is without upsampling board and saw some great things.
All the regulators in the upsampling dac appears to be adjustable regulators (LM317T-LM337T) instead of being fixed regulators. Adjustable regulators are better regulators than fixed regs.
When using output transformers, there is two unused regs, I will perhaps use them to feed digital and analog supplys separatly on the dac and CS8416.
The upsampling dac with Lundahls is now playing
As it is brand new, there will be a broken in time to do. I replaced the cheap RCA input with a BNC 75 ohm
I'm really surprized by the sound as is. I was afraid that the upsampling mode create somewhat a hard sound but it seems that the sound is great .
I will live sometime with this dac as is and later I will add an input digital transformer to try.
How can they sell at such a low price a board like this one ? This is really a good quality board with good parts
I made a comparaison with the other model which is without upsampling board and saw some great things.
All the regulators in the upsampling dac appears to be adjustable regulators (LM317T-LM337T) instead of being fixed regulators. Adjustable regulators are better regulators than fixed regs.
When using output transformers, there is two unused regs, I will perhaps use them to feed digital and analog supplys separatly on the dac and CS8416.
Attachments
Legarem
Can you tell us, how you connected the trannies? I see different resistors and capacitors.
Are you sure, you connected the left and right channel in phase? Did you remark, the solder pads are in the following order:
BTW: I love this hobby, but sometimes I really hate it!
Why?
One hour ago, I added a toggle switch and a BNC connector for SPDIF.
After this action, I had no more sound on the right channel.
Can absolutely not be related!
So, I was searching and searching, finally removing the rotary switch and the Studer trannies.
No sound on the right channel.
I took an old headphone from a crystal receiver: sound on pin 19 and 20, but not on the solder pad, where I attached the output.
Because I did not put the wires through the hole, just "glued" them to the pads. And I did also not use a breadboard to fix parts. Everytime I moved the whole thing from my desk to the workbench, I stressed a pad mechanically. One pad was slightly removed.
Franz
P.S.
Up to now I prefer the upsampling version with the Digitec trannies. It is just marvelous!
Can you tell us, how you connected the trannies? I see different resistors and capacitors.
Are you sure, you connected the left and right channel in phase? Did you remark, the solder pads are in the following order:
BTW: I love this hobby, but sometimes I really hate it!
Why?
One hour ago, I added a toggle switch and a BNC connector for SPDIF.
After this action, I had no more sound on the right channel.
Can absolutely not be related!
So, I was searching and searching, finally removing the rotary switch and the Studer trannies.
No sound on the right channel.
I took an old headphone from a crystal receiver: sound on pin 19 and 20, but not on the solder pad, where I attached the output.
Because I did not put the wires through the hole, just "glued" them to the pads. And I did also not use a breadboard to fix parts. Everytime I moved the whole thing from my desk to the workbench, I stressed a pad mechanically. One pad was slightly removed.
Franz
P.S.
Up to now I prefer the upsampling version with the Digitec trannies. It is just marvelous!
Franz Gysi said:
Hi Franz
No problems my transformers are correctly connected
I use a low pass filter before my transformers. Even if the transformer itself is a low pass filter, it is often recommended.
The R C combinaison at the secondary is recommended by Lundahl to gives better square wave with the LL1690
The new board is a joy to work. The solder is melting easily as opposed to the old board.
I tried many power transformers with these dacs and ended using STD EI core transformers, The sound is WAY better than toroidal transformers.
About upsampling. The listening done with the new dac reveals this:
1- Sound is smoother than the non upsampling dac
2- Seems to have better definition.
3- Soundstage seems to be even better
Drawbacks
1- Loss of immediacy of the sound
2- Reduced perceived attacks ?
3- Timbre doesn't seems to be as natural as non upsampling
Are these observations are related to upsampling vs non upsampling or new dac vs old dac ?
I will let it broken in some time before listening it in non upsampling mode.
Good luck with your dac
Attachments
